Cold and hot air blowing device for construction machinery

ABSTRACT

To provide a cold/warm air outlet assembly for construction a machine, said assembly being capable of fully meeting desires on the comfort of a working environment of an operator under air conditioning and use of air conditioning for a multiplicity of purposes, an upper outlet tube  2  and lower outlet tube  3  are formed into substantially tubular shapes having conical circumferential walls with walls, through which air outlets  20,30  are formed, being included as tilted walls. The upper outlet tube  2  is resiliently fitted and connected to the lower outlet tube  3,  and the lower outlet tube  3  is resiliently fitted and connected to a vertical part  11   a  of an air conditioner duct  11.  The upper and lower outlet tubes  2,3  are, therefore, turnable in horizontal direction at their connected parts. By operating air-direction control knobs  24,34  arranged in the air outlets  20,30  directed toward desired turned positions, the vertical directions of the internal fins  21   1 - 21   3   ,31   1 - 31   3  can be adjusted to cause cold/warm air to blow out in the desired directions, respectively.

TECHNICAL FIELD

[0001] This invention relates to a cold/warm air outlet assembly for anair conditioner. The cold/warm air outlet assembly is to be mounted on avertical part of an air conditioner duct which is arranged extendingupward in a front corner part of a cab of a construction machine such asa hydraulic excavator.

BACKGROUND ART

[0002] In a construction machine such as a hydraulic excavator, a cab isin a closed state surrounded at four sides and a ceiling thereof withglass plates, steel plates and/or the like to permit performingconstruction work even in severe weather environments such as rain,strong winds and snow. In construction work under the blazing sun inmidsummer, the interior of the cab in the closed state becomesconsiderably hot so that an operator of the construction machine isforced to work under severe conditions. Due to severe heat, the operatormay suffer from dehydration in some instances. JP 8-175156 A, forexample, discloses an invention on an air conditioner duct for ahydraulic excavator, which comprises three ducts extending from an airconditioner arranged on a floor behind an operator's seat, one having acold air outlet opening in an upper rear part of the operator's seat,another having a cold air outlet opening near a foot area below theoperator's seat, and the remaining one having a cold air outlet openingon a forward outboard side of the operator's seat.

[0003] The air outlet opening on the forward outboard side of theoperator's seat has a shape formed by cutting off a side wall of an airoutlet member which is in an upwardly tapered, substantially conicalshape. The air outlet member is turnably supported on a vertical part,which is arranged on an upstream side and extends in a verticaldirection, so that the air outlet opening can be directed in a desireddirection in a horizontal plane. Inside the air outlet opening whichopens in a somewhat upward direction, plural fins are connected togetherin parallel by connecting rods. By manipulating a knob connected to thefins, the fins can be adjusted in an interlocked stepless manner into adirection ranging from an upward direction to a downward direction. As aconsequence, the blowing direction of cold air can be set in any desiredvertical direction.

[0004] In a construction machine, such as a hydraulic excavator, with aheavy machine mounted thereon, a glass window covering the front of acab is arranged as wide as possible, generally extending over the entirearea of the front such that construction work can be performed whilefully watching and confirming the state of operation by a bucket, whichis arranged on a free end portion of the heavy machine to performloading of earth or sand, the ground, the working locations of workers,and the like. When the sun shines into the cab from the front in summer,the sunlight enters from an upper front through the front glass windowand the strong sunlight impinges primarily on the chest to feet of theoperator. To begin construction work under the strong sunlight insummer, the operator often presets the temperature of the airconditioner at a rather low level and its air volume at a maximum leveland, when the cab has become cool subsequent to performing work for awhile, resets the preset temperature and air volume to appropriatevalues. These values are automatically controlled in the case of an airconditioner of the type that the room temperature and air volume areautomatically controlled.

[0005] According to the above-mentioned conventional technique, thedirection of a cold wind blowing out of the air outlet can be set indesired vertical and horizontal directions by turning the air outletmember as desired and controlling the knob in the air outlet. If nosufficient refreshing feeling is available only with cold air from theair outlets arranged in the upper part behind the operator's seat andnear the foot area, respectively, the operator generally sets thedirection of the air outlet of the air outlet member such that the airoutlet is directed toward his face or chest, and then performs work. Inthis case, the operator's face and chest against which cold air isdirectly blown are cooled to such extent that he feels sufficientlycool. However, the lower half of the operator's body such as the femoraland pelvic regions, against which cold air does not blow directly andonly a wraparound wind blows indirectly, is exposed to the impingingsunlight and is heated by radiant heat. The operator, therefore, cannotenjoy much comfort. After the temperature of the cab has dropped to suchextent as the operator feels cold, the operator can feel comfortable forthe first time.

[0006] As the lower half of the operator's body, said lower half beingexposed to cold air only indirectly even after the temperature in thecab has changed to a stable level, tends to feel hot, the operator has atendency to set the cooling temperature of the air conditioner at arather low level so that the temperature in the cab may often be loweredbeyond necessity. If the operator adjusts the knob at the air outlet todirect the cold air toward the lower half of his body with a view toavoiding such a problem, the temperature of the upper half of his body,such as his face, is not lowered, thereby not only failing to obtaincomfort but also possibly overcooling the abdominal region so that theoperator may feel unwell. This problem is not limited to the time ofworking in a cooled environment in summer, but a similar situation alsoarises when working in a heated environment at the time of a coldweather such as winter.

[0007] When the humidity is high as in the rainy season or when theexterior temperature is low as in winter or the like, dew may be formedon the front glass window to cloud the same. To demist the front glasswindow, the operator may direct the air outlet member toward the frontglass window to blow cold air or warm air against the front glasswindow. During this demisting period, cold air or warm air is blown onlyindirectly against the operator so that the operator cannot feelcomfortable. Depending upon the convenience in proceeding with work, theoperator may have to proceed with the work while consulting with workersworking around the construction machine with an egress/ingress door,which is located in a side wall of the cab, kept open. In such a case,it is also necessary to direct the air outlet member toward anexit/entrance to shut off warm air or cold air which would otherwiseenter through the exit/entrance. This leads to an inconvenience that astream of air-conditioned air does not blow against the operator.

[0008] As the direction of cold or warm air blown out of the air outletcan be set in a desired direction in the conventional art, the comfortof the operator's working environment under air conditioning can besatisfied accordingly. Nonetheless, the conventional art is not fullysatisfactory in the comfort of a working environment under airconditioning especially in the hot or cold season or when airconditioning is used for a multiplicity of purposes, because cold orwarm air cannot be blown in a different direction concurrently withmaintaining the operator's whole body at a comfortable temperature orblowing cold or warm air against the operator.

[0009] The present invention has been completed with a view toovercoming such inconvenience in the conventional art, and has as anobject the provision of a cold/warm air outlet assembly for aconstruction machine, which can fully meet desires for the comfort of aworking environment of an operator under air conditioning and use of airconditioning for a multiplicity of purposes.

DISCLOSURE OF THE INVENTION

[0010] To solve the above-described problems, the present invention ischaracterized in that a plurality of air outlets are arranged in avertical direction of a casing to be mounted on a vertical part of anair conditioner duct, and directions of cold/warm air blowing out of therespective air outlets can be independently set in a vertical directionand a horizontal direction. Preferably, the casing may comprise a groupof plural small casings stacked in the vertical direction such that thesmall casings are slidingly turnable in a horizontal direction relativeto each other, and the small casings are each provided with at least oneair outlet formed therethrough. A circumferential wall of the casing isconstructed of a conical or upwardly tapered tubular member. Arestrictor may preferably be interposed on an upstream side of one ofthe air outlets, the one air outlet being located on a downstream side,to control a flow rate of the cold/warm air. At least one of the airoutlets may preferably be formed through an upwardly-directed, tiltedwall which forms at least a part of the circumferential wall of thecasing. With respect to each air outlet, plural fins may be arrangedturnably about a horizontal rod, and are interlocked by a connectingmember which connects the fins together.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 shows an air outlet assembly according to a firstembodiment of the present invention for an air conditioner duct, inwhich FIG. 1(a) is a plan view, FIG. 1(b) is a front view, and FIG. 1(c)is a cross-sectional view taken along line A-A.

[0012]FIG. 2 is an enlarged fragmentary view illustrating a fitted partbetween an upper outlet tube and a lower outlet tube in FIG. 1(c).

[0013]FIG. 3 is an enlarged fragmentary view illustrating a fitted partbetween a lower outlet tube and a vertical part in FIG. 1(c).

[0014]FIG. 4 shows an air outlet assembly according to a secondembodiment of the present invention, in which FIG. 4(a) is a plan view,FIG. 4(b) is a front view (b), and FIG. 4(c) is a cross-sectional viewtaken along line B-B.

[0015]FIG. 5 shows an upper outlet tube in the air outlet assemblyaccording to the second embodiment of the present invention, in whichFIG. 5(a) is a front view and FIG. 5(b) is a bottom view.

[0016]FIG. 6 shows a lower outlet tube in the air outlet assemblyaccording to the second embodiment of the present invention, in whichFIG. 6(a) is a plan view and FIG. 6(b) is a front view.

[0017]FIG. 7 shows an air outlet assembly according to a thirdembodiment of the present invention, in which FIG. 7(a) is a plan view,FIG. 7(b) is a front view, and FIG. 7(c) is a cross-sectional view takenalong line C-C.

[0018]FIG. 8 shows a restrictor plate relating to the third embodimentof the present invention, in which FIG. 8(a) is a plan view and FIG.8(b) is a cross-sectional view taken along line X-X.

[0019]FIG. 9 shows an air outlet assembly according to a fourthembodiment of the present invention, in which FIG. 9(a) is a plan view,FIG. 9(b) is a front view, and FIG. 9(c) is a cross-sectional view takenalong line D-D.

[0020]FIG. 10 shows an air outlet assembly according to a fifthembodiment of the present invention, in which FIG. 10(a) is a plan view,FIG. 10(b) is a front view, and FIG. 10(c) is a cross-sectional viewtaken along line E-E.

[0021]FIG. 11 is a drawing schematically illustrating an air outletassembly according to a sixth embodiment of the present invention.

[0022]FIG. 12 is a perspective view illustrating in a see-throughfashion an air conditioner in a cab of a hydraulic excavator, to whichthe first embodiment of the present invention has been applied.

[0023]FIG. 13 is a side view illustrating the air conditioner in the cabof the hydraulic excavator, to which the first embodiment of the presentinvention has been applied.

[0024]FIG. 14 is a plan view illustrating the air conditioner in the cabof the hydraulic excavator, to which the first embodiment of the presentinvention has been applied.

[0025]FIG. 15 is a side view illustrating an air conditioner in a cab ofa hydraulic excavator, to which a seventh embodiment of the presentinvention has been applied.

[0026]FIG. 16 is a plan view illustrating the air conditioner in the cabof the hydraulic excavator, to which the seventh embodiment of thepresent invention has been applied.

BEST MODE FOR CARRYING OUT THE INVENTION

[0027] With reference to the drawings, the embodiments of the presentinvention will hereinafter be described in detail.

[0028]FIG. 12, FIG. 13 and FIG. 14 are the perspective view, side viewand plan view, which illustrate in the see-through fashion the airconditioner in the cab of the hydraulic excavator, to which the firstembodiment of the present invention has been applied. These drawingsshow an air outlet assembly 1 for blowing cold/warm air, which has beendelivered from an air conditioner, into a front part of the cab; the cab7 in which an operator operates the hydraulic excavator; the airconditioner 8 arranged in a rear part of the cab 7; an operator's seat10 on which the operator sits; air conditioner ducts 11,12,13 forguiding cold/warm air, which has been supplied from the air conditioner8, forward from a point above a flooring on a right side of the cab 7,forward and downward from a point above a central flooring, and rearwardand upward along a right side wall, respectively; a vertical part 11 aof the air conditioner duct 11, said vertical part 11 a being a part ofthe air conditioner duct 11 extending forward from the point above theflooring on the right side and extending in a vertical direction in afront right corner and supporting the air outlet assembly 1; an opening11 b opening in a top portion of the vertical part 11 a and connected toa bottom part of the air outlet assembly 1; a front window 71 formed ofa glass plate substantially covering the front of the cab 7; theflooring 72 covering a floor, left and right side walls; a rear wall 73covering the rear of the cab 10; a ceiling 74; and a side window 75.

[0029] An unillustrated egress/ingress door is arranged in the left sidewall as viewed from the operator's seat 10 in the cab 7, and the airconditioner duct 11 which extends toward a front right corner of the cab7 is arranged at such a position that it does not interfere with aningress or egress of an operator who is entering or leaving by openingthe egress/ingress door. The air outlet assembly 1 arranged on a freeend part of the air conditioner duct 1 is to blow cold/warm air directlyagainst the operator, the front window 71 and the like, whereas the airconditioner ducts 12,13 are to blow cold/warm air, which has beensupplied from the air conditioner 8, indirectly from a lower part of thecab 7 toward the front and from a rear part toward the-ceiling 74,respectively. The vertical part 11 a of the air conditioner duct 11 andthe air outlet assembly 1 attached to the upper end of the vertical partare arranged in a lower part of a corner section between the frontwindow 71 and the right side wall 73. The vertical part 11 a and the airoutlet assembly 1, therefore, do not interfere at all with theoperator's view, and further, do not interfere with open/close operationof the front window 71 which is slidably openable and closable in thevertical direction.

[0030]FIG. 1 includes the plan view (a) of the air outlet assembly 1according to the first embodiment of the present invention arranged onan upper end portion of the air conditioner duct 11, its front view (b),and its vertical cross-sectional view (c) taken along the cutting-planeline A-A in the plan view (a). In these drawings, there are shown anupper outlet tube 2 and lower outlet tube 3 which together constitutethe air outlet assembly 1, are in substantially cylindrical shapeshaving conical circumferential walls, respectively, and include, astilted walls, circumferential walls in which cold/warm air outlets to bedescribed subsequently herein are formed; the cold/warm air outlets20,30 formed in the tilted walls of the circumferential walls of theupper outlet tube 2 and lower outlet tube 3, said tilted walls beingdirected somewhat upward; and fins 21 ₁-21 ₃,31 ₁-31 ₃ turnably arrangedas sets of 3 fins, one set above the other, inside the upper outlet tube2 and lower outlet tube 3 at positions facing the air outlets 20,30.

[0031] There are also shown brackets 22,32 arranged in pairs in theupper outlet tube 2 and lower outlet tube 3 at opposite sides of the airoutlets 20,30, respectively, and turnably supporting the three fins 21₁-21 ₃,31 ₁-31 ₃ in the upper outlet tube 2 and lower outlet tube 3;connecting rods 23,33 turnablly connected to rear end portions of thethree fins 21 ₁-21 ₃,31 ₁-31 ₃ with equal intervals therebetween suchthat the fins 21 ₁-21 ₃,31 ₁-31 ₃ are kept in parallel with each otherand are interlocked with each other upon turning them; and air-directioncontrol knobs 24,34 fixed to the central fins 212,312 out of the threefins 21 ₁-21 ₃,31 ₁-31 ₃ and operable when an operator wants to turn thefins 21 ₁-21 ₃,31 ₁-31 ₃ in a vertical direction to change verticaldirections of cold/warm air from the air outlets 20,30.

[0032]FIG. 2 and FIG. 3 are the enlarged fragmentary views, whichillustrate the fitted part between the upper outlet tube 2 and the loweroutlet tube 3 and the fitted part between the lower outlet tube 3 andthe vertical part 11 in the vertical cross-sectional view (c) takenalong the cutting-plane line A-A in the plan view of FIG. 1. In thesedrawings, there are illustrated an outer flange 2 a formed on a lowerend of the upper outlet tube 2 such that the outer flange is in a formof a ring of the same diameter as a maximum diameter of the lower endportion of the lower outlet tube 3 and extends in a lateral direction; acollar 2 b formed on an upper portion of the outer flange 2 a of theupper outlet tube 2 such that an upper surface of the collar lies in asubstantially horizontal plane and the collar extends forward from theabove-described tilted wall; an inner flange 3 a formed on an upper endportion of the lower outlet tube 3 such that the inner flange is in theform of a disk with a diameter slightly smaller than an inner diameterof the outer flange 2 of the upper outlet tube 2 and extends in alateral direction; a stepped portion 3 b formed as a tubular surface ofa slightly smaller diameter as a result of a retreat of a lower side ofa peripheral end part of the inner flange 3 a in a radial direction; anouter flange 3 c formed on a lower end portion of the lower outlet tube3 such that the outer flange 3 c has substantially the same diameter asthe outer flange 2 a and extends in a lateral direction; and a steppedportion 3 d formed inside the outer flange 3 c such that the steppedportion has a circular circumferential wall of the same diameter as theopening 11 b of the vertical part 11 a.

[0033] Also shown are a synthetic-resin-made locking ring 4, which isresistant to heat and does not undergo thermal deformation, is high inresilience, is in the form of a ring-shaped band and is fixedly adheredon an inner circumferential surface of the outer flange 2 a of the upperoutlet tube 2; a synthetic-resin-made fitting ring 5, which is resistantto heat and does not undergo thermal deformation, is high in resilience,is in the form of a ring-shaped band, is fixedly adhered on the steppedportion 3 d formed on an inner circumferential surface of the lower endportion of the lower outlet tube 3 and has an outer circumferential wallof the same diameter as the opening 11 b of the vertical part 11 a; clawportions 41 formed by bending a lower portion of the locking ring 4 in avertical direction, each of said claw portions 41 having across-sectional shape in the form of a wedge projecting toward an innercircumference; dividing slits 42 formed at equal intervals in the lowerportion of the locking ring 4 to facilitate resilient deformations ofthe claw portions 41 and dividing the claw portions 41 equally in thecircumferential direction; claw portions 51 formed by bending a lowerportion of the locking ring 5 in a vertical direction, each of said clawportions 51 having a cross-sectional shape in the form of a wedgeprojecting toward an outer circumference; and dividing slits 52 formedat equal intervals in the lower portion of the locking ring 5 tofacilitate resilient deformations of the claw portions 51 and dividingthe claw portions 51 equally in the circumferential direction.

[0034] To complete the air outlet assembly 1 and assemble the air outletassembly 1 onto the vertical part 11 a of the air conditioner duct 11,the upper outlet tube 2 is pressed with somewhat strong force into thelower outlet tube 3. The inner flange 3 b of the lower outlet tube 3 isthus fitted while outwardly pressing the projections of the clawportions 41 of the locking ring 4. As soon as the inner flange 3 b movespast the claw portions 41, the inner flange 3 b reaches a position ofcontact on a back side of the collar 2 b and inside the outer flange ofthe upper outlet tube 2 without any interruption so that by theprojections of the claw portions 41, the upper outlet tube 2 is lockedturnably in a horizontal direction. When the lower outlet tube 3 ispressed with somewhat strong force into the vertical part 11 a of theair conditioner duct 11, the fitting ring 5 adhered on the innercircumferential surface of the outer flange 3 c on the lower end portionof the lower outlet tube 3 is fitted into the opening 11 b in thevertical part 11 a of the air conditioner duct 11 while being subjectedto a resilient deformation that the projections of the claw portions 51are pressed inward. Accordingly, the lower outlet tube 3 is turnablyfitted by the projections of the claw portions 51.

[0035] After the completion of the air outlet assembly 1 and theassembly of the air outlet assembly on the vertical part 11 a of the airconditioner duct 11 are completed as described above, the projections ofthe claw portions 41 of the locking ring 4 adhered on the innercircumferential wall of the outer flange 2 of the upper outlet tube 2are allowed to fit in the stepped portion 3 b of the lower outlet tube 3to clinch the inner flange 3 b and further, the projections of the clawportions 51 b of the fitting ring 5 are allowed to outwardly extend fromthe lower edge of the opening 11 of the vertical part 11 a of the airconditioner duct 11 and are brought into engagement. As a result, theupper outlet tube 2 and the lower outlet tube 3 are firmly and turnablyfitted onto the lower outlet tube 3 and the vertical part 11 a of theair conditioner duct 11, respectively, and therefore, do not fall offeasily.

[0036] Because, as mentioned above, the upper outlet tube 2 is turnablyattached to the lower outlet tube 3 and the lower outlet tube 3 isturnably attached to the vertical part 11 a of the air conditioner duct11, cold/warm air can be blown out by turning the two air outlets 20,30of the upper outlet tube 2 and lower outlet tube 3 in the air outletassembly in desired two horizontal directions, respectively, andfurther, by manipulating the air-direction control knobs 24,34 to directthe vertical directions of the internal fins 21 ₁-21 ₃,31 ₁-31 ₃ indesired directions, respectively. Incidentally, the manipulation of theair-direction control knobs 24,34 causes the central fins 21 ₂,31 ₂ toturn about pivots on the brackets 22,32, and via the connecting rods23,33 turnably attached to rear end portions of the central fins, theirturning motions are transmitted to the upper and lower fins 21 ₁,21 ₃,31₁,31 ₃ so that the fins are interlocked.

[0037] When the strong sunlight in midsummer impinges from the upperfront, for example, the temperature in the closed cab 7 may rapidly riseinto a state of scorching heat unless the air conditioner 8 is operated.The operator, therefore, turns on the air conditioner 8 to lower thetemperature of air within the cab 7 with cold air blowing out of thefixed air conditioner ducts 12,13 and at the same time, directs theupper outlet tube 2 and lower outlet tube 3, which serve to performdirect blowing of cold air, toward himself and manipulates theair-direction control knobs 24,34 of the upper outlet tube 2 and loweroutlet tube 3 to adjust the directions of cold air, for example, suchthat cold air is blown toward his face from the air outlet 20 of theupper outlet tube 2 and toward the knee region from the air outlet 30 ofthe lower outlet tube 3, respectively. This adjustment makes it possibleto intensively cool parts of the body, against which the sunlightdirectly impinges in particular, so that the operator can be fullysatisfied in connection with the air conditioning of the cab 7.

[0038] When the humidity is high as in the rainy season or thetemperature is low as in winter, the front window 71 or the like of thecab 7 may be cooled to form dew on its inner surface so that it may beclouded. In such a case, the operator can perform demisting, forexample, by directing the air outlet 30 of the lower outlet tube 3toward the front window 71 or the like while keeping the air outlet 20of the upper outlet tube 2 directed toward himself to make him feelcool. This applies equally when work is performed with theegress/ingress door kept open. Cold air w, which flows into the airoutlet assembly 1 from the air conditioner duct 11, separates to the twoair outlets, the air outlet 20 of the upper outlet tube 2 and the airoutlet 30 of the lower outlet tube 3 and then blows out to the outside.As the volume ratio of the respective air flows is determined by theextents of tapering of the conical shapes which are formed by thecircumferential walls of the upper outlet tube 2 and the lower outlettube 3, the opening ratio of the air outlet 20 to the air outlet 30, theshape of an upper part of the upper outlet tube 2, and the like, thevolume ratio of the respective air flows can be determined by settingthese conditions as desired. According to the results of an experiment,setting of the volume ratio of air flows blown out of the upper andlower outlet tubes at 6 to 4 has been found to provide an operator withthe best comfort.

[0039] In this embodiment, the circumferential walls on the sides of theair outlets 20,30 of the upper outlet tube 2 and lower outlet tube 3 areformed as tilted walls. This is to adequately set the above-mentionedair volume ratio and also to promote smooth flow of cold wind blowingout in an obliquely upward direction when the fins 21 ₁-21 ₃,23 ₁-23 ₃are directed upward. Further, the arrangement of thelaterally-extending, disk-shaped, outer flange 2 a and the inner flange3 a, which is fitted with the outer flange 2 a, at the connecting partbetween the upper outlet tube 2 and the lower outlet tube 3 is toimprove the attractiveness of the external appearance of the air outletassembly 1, to make the upper outlet tube 2 and the lower outlet tube 3turnable at the connecting part, to meet the need that their slidingportions have to be formed into circular shapes, and also to facilitaterecognizing that the upper outlet tube 2 is turnable relative to thelower outlet tube 3.

[0040] In this embodiment, the connection between the upper outlet tube2 and the lower outlet tube 3 and that between the lower outlet tube 3and the vertical part 11 a of the air conditioner duct 11 are realizedby the locking structures making use of resilient deformations ofprojections of the claw portions 41,51 of the locking ring 4 and fittingring 5, respectively. These connecting structures are merelyillustrative, and any structures may be employed insofar as they performa similar function. Further, the contour shapes of the upper outlet tube2 and lower outlet tube 3 are in substantially cylindrical forms havingconical circumferential walls. However, their counter shapes may beformed into desired shapes insofar as the connecting sliding portionbetween both of the outlet tubes and also that between the lower outlettube 3 and the vertical part 11 a of the air conditioner duct 11 areformed in circular shapes.

[0041]FIG. 4 includes the plan view (a) of the air outlet assembly 1according to the second embodiment of the present invention arranged asan upper end part of the air conditioner duct 11, its front view (b) andits vertical cross-sectional view (c) taken along the cutting-plane lineB-B in the plan view (a), FIG. 5 includes the front view (a) and bottomview (b) of the upper outlet tube 2, and FIG. 6 includes the plan view(a) and front view (b) of the lower outlet tube 3. These drawingsillustrate a bottom wall 25 of the upper outlet tube 2; three legs 26arranged on and extending from the bottom wall 25 of the upper outlettube 2 at three locations adjacent to a circumferential edge of thebottom wall such that, as shown in FIG. 5(b), the three legs arearranged at non-equal angular intervals of from 100° to 140° and theirfree ends are formed as flat portions bent outward; a fitted opening 35formed through an upper wall of the lower outlet tube 3 with such aninner diameter that the circumferential edge of the fitted openingremains in sliding contact with base portions of the three legs of theupper outlet tube 2; and three cut-off portions 35 a formed in an innercircumferential portion of the fitted opening 35 at positions facing thethree legs 26 of the upper outlet tube 2. In these drawings, elements ofstructure which are identical or can be considered identical to thecorresponding elements of structure in the first embodiment areidentified by like reference numerals and their repetitive descriptionswill be omitted.

[0042] To complete the air outlet assembly 1, the upper outlet tube 2 isheld on an upper part of the lower outlet tube 3. The upper outlet tube2 and the lower outlet tube 3 are brought into angular registration suchthat the positions of arrangement of the three legs 26 arrangedextending from the bottom wall 25 and the positions of arrangement ofthe three cut-off portions 35 a formed in the inner circumferentialportion of the fitted opening 35 in the lower outlet tube 3 preciselyregister with each other, and the upper outlet tube 2 is pressed into anupper part of the lower outlet tube 3. As a result, the legs 26 of theupper outlet tube 2 are fitted into the corresponding cut-of portions 35a of the lower outlet tube 3. Subsequent rotation of the upper outlettube 2 over a predetermined angle brings upper surfaces of the flatportions of the legs 26 and a lower surface of the upper portion of thelower outlet tube 3 into sliding contact, and by the resultingfrictional force, the upper outlet tube 2 is held at the rotatedposition. Even if the upper air outlet 2 is caused to turn relative tothe lower outlet tube 3, the upper outlet tube 2, therefore, does notfall off from the lower outlet tube 3 as long as the positions ofarrangement of the legs 26 on the upper outlet tube 2 and the positionsof arrangement of the cut-off portions 35 a in the lower outlet tube 3are not brought into precise registration. As is appreciated from theforegoing, this embodiment makes it possible to simply and easily makethe construction of the connecting part between the upper outlet tube 2and the lower outlet tube 3, so that the assembly and disassembly workof the air outlet assembly 1 can be performed with extremely ease.

[0043] In this embodiment, the lower outlet tube 3 is in a substantiallycylindrical form. Accordingly, its air outlet 30 is formed in a verticalwall rather than in a tilted wall. As the lower outlet tube 3 is in asubstantially cylindrical form as mentioned above, its internal diametercan be dimensioned large compared with the upper outlet tube 2. Thismakes it possible to set relatively large the volume ratio of an airflow through the air outlet 30 of the lower outlet tube 3 to an air flowthrough the air outlet 20 of the upper outlet tube 2. Since the airoutlet 30 of the lower outlet tube 3 is formed in the verticalcircumferential wall, warm air can be effectively blown out, forexample, when it is desired to blow out warm air intensively to the footregion of an operator. By suitably adjusting the shapes of the upperoutlet tube 2 and lower outlet tube 3, the opening ratio of the airoutlet 20 to the air outlet 30 and/or the like as mentioned above, thevolume ratio of cold/warm air blown out through the air outlet 20 tothat blown out through the air outlet 30 can be easily set.

[0044]FIG. 7 includes the plan view (a) of the air outlet assembly 1according to the third embodiment of the present invention arranged asan upper end part of the air conditioner duct 11, which permits easysetting of a volume ratio of cold/warm wind blown out through an airoutlet 20 to that blown out through an air outlet 30, its front view (b)and its vertical cross-sectional view (c) taken along the cutting-planeline C-C; and FIG. 8 includes the plan view (a) of the restrictor plateand the vertical cross-sectional view (b) taken along the cutting-planeline X-X. In these drawings, there are illustrated the restrictor plate(6) interposed between the upper outlet tube 2 and the lower outlet tube3 to restrict the flow rate of cold/warm air from the lower outlet tube3 to the upper outlet tube 2 in accordance with the area of its opening;three cut-off portions 6 a formed in an outer circumferential portion ofthe restrictor plate 6 at three locations facing three legs 26 on theupper outlet tube 2; and an air-volume-adjusting restricted hole 6 bcentrally formed in a concentric form through the restrictor plate 6.

[0045] This embodiment is considerably different from the secondembodiment in that the restrictor plate 6 is interposed between theupper outlet tube 2 and the lower outlet tube 3. To complete the airoutlet assembly 1, the upper outlet tube 2 is held upside down to makethe bottom wall 25 face upward, and the restrictor plate 6 is then heldon the bottom wall 25. The restrictor plate 6 is brought into angularregistration such that the positions of arrangement of the three legs26, which extend upright on the bottom wall 25 of the upper outlet tube2, and the positions of arrangement of the three cut-off portions 6 aformed in the outer circumferential portion of the restrictor plate 6precisely register with each other to have the restrictor plate 6 fittedon the legs 26 of the upper outlet tube 2. Subsequently, the upperoutlet tube 2 is connected with the lower outlet tube 3 in the samemanner as the manner mentioned above with respect to the formerembodiment. Advance provision of plural restrictor plates 6 different inthe restricted hole 6 b permits performing an adjustment to a desiredair volume ratio without making changes to the shapes or the like of theupper outlet tube 2 and lower outlet tube 3 by simply selecting one ofthe restrictor plates 6, which is suited for a desired air volume ratio,and assembling it in the air outlet assembly 1.

[0046]FIG. 9 includes the plan view (a) of the air outlet assembly 1according to the fourth embodiment of the present invention arranged asan upper end part of the air conditioner duct 11, its front view (b),and its cross-sectional view taken along cutting-plane line D-D in theplan view (a). In FIG. 9(c), sign 2 a designates a curved rear wallwhich forms a gently curved surface in an upper outlet tube 2. Thisembodiment is different from the third embodiment in that an upperoutlet tube 2 is provided at an upper rear part thereof with this curvedwall. In this embodiment, the rear part of the upper outlet tube 2 isformed as the curved rear wall 2 a which presents the gently curvedsurface. A flow or cold/warm air, which has blown upward through thevertical part 11 a of the air conditioner duct 11, can hence be smoothlychanged by the curved rear wall 2 a into a flow of cold/hot air thatblows forward.

[0047]FIG. 10 includes the plan view (a) of the air outlet assembly 1according to a fifth embodiment of the present invention arranged as anupper end part of the air conditioner duct 11, its front view (b), andits cross-sectional view taken along cutting-plane line E-E. Thesedrawings depict an outlet tube 9 making up an air outlet assembly 1 by asingle casing; a semicircular support collar 15 arranged on a frontside, in a substantially central part as viewed in a vertical direction,within the outlet tube 9 with a front edge thereof integrally fixed onan inner circumferential wall of the outlet tube 9; a box-shaped case 16supporting on both left and right sides thereof a pair of brackets 22 attheir upper end portions and lower end portions, and supported turnablyin a horizontal direction; and support pins 17,18 arranged extendingfrom central parts of an upper and lower walls of the box-shaped case 16and turnably supported on a top wall of the outlet tube 9 and the uppersurface of the support collar 15, respectively. Like the lower outlettube 3 in the first embodiment, claw portions 51 of a fitting ring 5which is fixedly adhered on an inner circumferential surface of a lowerpart of the outlet tube 9 are fitted in the opening 11 b of the verticalpart 11 a of the air conditioner duce 11, so that by projections of theclaw portions 51, the outlet tube 9 is fitted turnably in a horizontaldirection.

[0048] As the upper and lower air outlets 20,30 are both formed in thefront wall of the single outlet tube 9 in this embodiment, thehorizontal directions of cold/warm air blown out of the air outlets20,30 are basically the same as the directions in which the air outlets20,30 are directed. It is, however, to be noted that the box-shaped case16 is turnable in a horizontal direction owing to the provision of thesupport pins 17,18. Therefore, the direction of cold/warm air, whichblows out of the air outlet 20 after flowing through the box-shaped case16, can be changed to certain extent in a leftward or rightwarddirection depending upon the horizontal direction of the box-shaped case16. In this embodiment, fins which are arrayed in a vertical directionare not attached to the box-shaped case 16. If such vertically arrayedfins are attached to the box-shaped, however, a change in the directionof cold/warm air, which blows out of the air outlet 20, depending uponthe horizontal direction of the box-shaped case 16 will become morepronounced. As is appreciated from the foregoing, this embodiment alsoallows to change the directions of cold/warm air, which blows out of theupper and lower air outlets 20,30, in both. horizontal and verticaldirections by adjusting the turned position of the outlet tube 9, theturned position of the box-shaped case 16 and the vertical directions ofthe fins 21 ₁-21 ₃,31 ₁-31 ₃ as desired.

[0049]FIG. 11 is the schematic view of the air outlet assembly 1according to the sixth embodiment of the present invention arranged asan upper end part of the air conditioner duct 11. In the drawing,numeral 2′ designates a middle outlet tube, which is interposed betweenan upper outlet tube 2 and a lower outlet tube 3 and has a substantiallysimilar shape as the upper outlet tube 2. As apparent from the drawing,this embodiment is characterized in that the three outlet tubes arearranged into a stacked structure. Owing to the adoption of such astructure, the number of outlets for cold/warm air, each of said outletsbeing capable of changing the direction of cold/warm air in bothhorizontal and vertical directions, can be increased by one to three. Itis, therefore, possible to intensively cool or warm a greater number ofplaces or regions. Needless to say, the number of stacked outlet tubescan be increased further.

[0050]FIG. 15 and FIG. 16 are the side view and plan view, in each ofwhich the air conditioner in the cab of the hydraulic excavator, towhich the seventh embodiment of the present invention has been applied,is observed in a see-through fashion. These drawings illustrate an airoutlet assembly 1′ arranged in a front left corner of the cab 7 at aposition laterally symmetrical with the air outlet assembly 1 and havingthe same shape as the air outlet assembly 1; and a vertical part 11 a′branched out from a rising part of the air conditioner duct 11,extending along a lower front end of the cab 7, rising in a verticaldirection in the front left corner and arranged at a position laterallysymmetrical with the vertical part 11 a. As the air outlet assembly 1′is additionally arranged in the front left corner of the cab 7 at theposition laterally symmetrical with the air outlet assembly 1 asdescribed above, this embodiment is doubled in the number of air outletassemblies and can blow cold/warm air from different directions againstan operator to cool or warm the operator evenly on both left and rightsides.

[0051] Industrial Applicability

[0052] As has been described above, according to the present invention,a plurality of air outlets are arranged in a vertical direction of acasing, and directions of cold/warm air blowing out of the respectiveair outlets can be independently set in a vertical direction and ahorizontal direction. Therefore, the cold/warm air—which blows out ofthe upper and lower air outlets, respectively—can be set in desiredvertical and horizontal directions, thereby making it possible to fullymeet desires on the comfort of a working environment of an operatorunder air conditioning and use of air conditioning for a multiplicity ofpurposes.

[0053] According to the present invention, the circumferential wall ofthe casing may be constructed of a conical or upwardly tapered tubularmember. Therefore, the ratio of volumes of cold/warm air which blows outof the respective air outlets, can be set at a desired value by suitablysetting the tapered shape of the casing.

[0054] According to the present invention, the casing may comprise aplurality of small casings stacked in the vertical direction such thatthe small casings are slidingly turnable in a horizontal directionrelative to each other, and the small casings may each be provided withat least one air outlet formed therethrough. Therefore, the horizontalblowing directions of cold/warm air can be changed to desired directionsby the simple construction.

[0055] According to the present invention, with respect to each airoutlet, plural fins may be arranged turnably about a horizontal rod andmay be interlocked by a connecting member which connects the finstogether. Therefore, cold/warm air which blows out of each air outlet isallowed to flow out as a laminar flow.

[0056] According to the present invention, a restrictor may beinterposed on an upstream side of one of the air outlets, said one airoutlet being located on a downstream side, to control a flow rate ofcold/warm air. Therefore, the ratio of a flow rate of cold/warm air onan upstream side of the restrictor to a flow rate of cold/warm air on adownstream side of the restrictor can be easily adjusted.

[0057] According to the present invention, at least one of the airoutlets may be formed through an upwardly-directed, tilted wall whichforms at least a part of the circumferential wall of the casing.Therefore, cold/warm air which blows out of the air outlet can flow outsmoothly.

1. A cold/warm air outlet assembly for a construction machine, saidassembly including a casing for being arranged on a vertical part of anair conditioner duct arranged in a cab such that said vertical partextends upwardly in a front corner section of said cab to guide acold/warm air supplied from an air conditioner, an air outlet formed ina circumferential wall of said casing and capable of allowing saidcold/warm air to blow out in a sideward direction, and fins arranged insaid air outlet turnably at least about a horizontal rod to cause saidcold/warm air to blow out in a desired direction, characterized in thata plurality of air outlets as defined above are arranged in a verticaldirection of said casing, and directions of cold/warm air blowing out ofsaid respective air outlets can be independently set in a verticaldirection and a horizontal direction.
 2. A cold/warm air outlet assemblyaccording to claim 1, wherein said circumferential wall of said casingis constructed of a conical or upwardly tapered tubular member.
 3. Acold/warm air outlet assembly according to claim 1, wherein said casingcomprises a plurality of small casings stacked in said verticaldirection such that said small casings are slidingly turnable in ahorizontal direction relative to each other, and said small casings areeach provided with at least one air outlet formed therethrough.
 4. Acold/warm air outlet assembly according to claim 1, wherein with respectto each air outlet, plural fins as defined in claim 1 are arrangedturnably about a horizontal rod, and are interlocked by a connectingmember which connects said fins together.
 5. A cold/warm air outletassembly according to claim 1, wherein a restrictor is interposed on anupstream side of one of said air outlets, said one air outlet beinglocated on a downstream side, to control a flow rate of said cold/warmair.
 6. A cold/warm air outlet assembly according to claim 1, wherein atleast one of said air outlets is formed through an upwardly-directed,tilted wall which forms at least a part of said circumferential wall ofsaid casing.